PVs and the best electricity tariff

Aaronsdad

I've looked elsewhere on the forum and found a locked thread which didn't have the answer.
Having just had a 3kw PV system installed. Would I be better off switching to an economy 7 tariff for cheap electricity once the sun has gone down? Will my 3kw system provide enough electricity during the day to offset the higher cost of daytime electricity?

My wife and I both work from home and have 4 kids (3 at school).

I currently have no breakdown of my daily or evening usage, my heating is gas fired as is my water heater ( albeit i am considering an immersun or similar device for electrical immersion heating).

Cardew

Welcome to the forum.


The purpose of going on Economy 7 is mainly to use it for heating and hot water, as well as appliances at night. This is to combat the higher cost of electricity for the other 17 hours.


As you have gas, that largely takes care of the heating and hot water as it will be cheaper to use that fuel than even off-peak electricity.


Your solar output during the day will go some way toward running appliances.


As you are home during the day you are likely to use quite a bit of electricity.


So all in all I cannot think of a single reason why you should contemplate getting Economy 7.

thenudeone

I would wait and see how your electricity usage changes before changing to E7. Most people never get anywhere near to using most of their solar energy whilst its being produced. Even if you have washers, driers, and heaters on timers, the variability of the weather means you'll still be out of sync.

macman

E7 doesn't provide a cheaper rate 'when the sun goes down'-it provides it between typically midnight and 7am. So all your evening and morning consumption will probably still be be on peak rate, unless you keep atypical hours.

Aaronsdad

thanks all.
I wont rush into anything then. I'll do a bit of monitoring but the thought of the cheaper rate kicking in at midnight probably will be the decider.